The foam extrusion of thermoplastic resin is a well-known and established manufacturing process for insulation materials. On the other hand, the continuous manufacturing of insulation materials made of thermosets is limited to liquid thermoset systems, which exhibit very good insulation properties but poor mechanical characteristics. Because of the rising demand to lower CO2 emissions, the prospect of new insulation materials with mechanical supporting characteristics to reduce thermal bridges in construction leads to new approaches in material, process and part development. Free flowing phenolic molding compounds exhibit high static mechanical and good insulation properties and they can be suitable for processing via co-rotating twin screw extruders. After further development of the underlying extrusion process to ensure stable processing conditions over longer periods of time, the challenge of the temperature and time induced curing of the phenolic resin on the process stability could be overcome. Subsequently, several variations of processing conditions were performed. For this research, we investigated processing influences of the extrusion on the properties of the manufactured parts. Especially the overall size and deformation of the pores and the formation of possible foam gradients over the part thickness were examined and compared. The results show that pore structures and in return part properties such as density and mechanical properties are vastly influenced by the processing conditions.